


Mortal

by TheArcReactor (Ashkka)



Series: Marvel One-Shots [1]
Category: Avengers Assemble (Cartoon), Captain America - All Media Types, Iron Man - All Media Types, Marvel, The Avengers (Marvel) - All Media Types
Genre: Arc Reactor Failure, Arc Reactor Issues, Character Death, Death, Emotional, M/M, Protective Steve Rogers, Tony Stark Has A Heart
Language: English
Status: Completed
Published: 2017-11-12
Updated: 2017-11-12
Packaged: 2018-10-19 22:57:23
Rating: Teen And Up Audiences
Warnings: Graphic Depictions Of Violence, Major Character Death
Chapters: 1
Words: 3,731
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/10649808
Author URL: https://archiveofourown.org/users/Ashkka/pseuds/TheArcReactor
Summary: With Ultron on the loose and out for blood, it was only expected that there be casualties.Steve Rodgers has seen many deaths, he'd prepared to see more during the battle. But you can never really prepare to see the people you care about die, can you?Especially if that one person who dies is the person you love.





	Mortal

**Author's Note:**

> Major Update as of 11/12/17. Went through and basically rewrote parts of it, along with going and correcting all those grammatical errors. LOTS more detail, my goodness my writing was so... monotone? (is that the right word). Well, hopefully, you all have a much easier time reading it! :)  
> \- basically I reworked the entire thing-  
>  
> 
> This piece is short, but sweet. It was difficult to write for me because I love both characters so much and I hate to see one go...

_The Avengers had been fighting Ultron for almost an hour now and Steve was beginning to lose hope._

_Robots swarmed all over Ultron's base of operations, making it impossible to get close to it. Several times, the Avengers made a rush for the compound but were pushed back by the sheer number of enemies._

_So then came a plan: Steve and Tony were to infiltrate the compound and dismantle the missile in a covert mission, while the other Avengers lured out the main force. This would be extremely dangerous, as their opponent had both an army and a genius creator (Tony)._

_Due to the nature of the task at hand, Tony could not wear his armor, but rather a uniform similar to what Hawkeye or Widow wore. The stubborn billionaire had insisted that he be the one to go, despite Steve's strong objection. The main reason was his knowledge of Ultron's tech. If it had been that alone, Steve's argument might have stood a chance. Unfortunately, Tony had spewed another laundry-list of reasons why he -and only he- should be the one going. The following argument between the two had made Natasha burst into a bout of very unexpected laughter. She'd joked that they sounded like a married couple. NeitherTony nor Steve had seen the humor of statement, but for some reason, the rest of the team -minus Vision- had found it very funny._

_By the end of the hour, it had been decided that the "married couple" be sent into the compound, under the agreement that they wouldn't kill each other first._

_There were several plans: The first was to take a device all the way in and plant it onto the missile, deactivating it. The other was more difficult. It was a small object that Tony and Vision had developed months earlier. It would lock down Ultron and keep him in one body, placing a virus in all the metal soldiers he had. The only problem was that the body had to be the one that Ultron inhabited, otherwise it would not work correctly. The other issue was that Ultron could not be given the opportunity to escape to another form. The third option was Tony's idea: improvise, and that counted for more than one plan in itself because... there really wasn't one._

_Tony remained optimistic about the mission, geeking out about the chance to use the new tools that he had whipped up, talking to Steve excitedly about its various functions and properties. After a few minutes, Steve had gathered enough strength to smile._

* * *

 

Ultron's robots were like large metallic ants. Even inside the compound, there were swarms of them, many of them grouped in the larger rooms or stalking through the hallways in small pods. After fighting several bot waves, Steve had finally began to realize that huge danger of Ultron's forces. Outside, with a larger team. fatigue had not been such a huge issue. In such a large team, it was possible to switch out and get a short break. With only two people, it was much more difficult. There was himself: A man with a sidearm -which did close to nothing- and his shield, and then Tony: without a suit, virtually defenseless if attacked, and armed with his brains, a sidearm similar to Steve's, and a small laser rifle. Granted, the laser rifle did a lot against robots, but it was nowhere near in efficiency to Steve's shield. 

After fighting through waves and waves of robots, Steve and Tony finally reached the chamber with the bomb. Both of them had sustained minor injuries and were exhausted. The plan seemed to be working, which was what worried Steve. Plans were made to work. When they didn't work, things got messy, but when they worked  _too_ well... well then, that was another story altogether. Especially if the opponent was super strong, smart, and an AI programmed by one of the smartest men in the world (not that Steve would ever give Tony the satisfaction of telling him so).

The bomb sat in the middle of the chamber, surrounded by the metal casings of an old missile. An odd humming sound filled the air. A slight indentation was set into the cement floor below, making a large circle around where the bomb was, that spanned a good fifty feet. Altogether, the area looked like a giant bowl, with the rim starting several feet from the doorway. The ceiling was constructed so that it could be opened up upon launch. Small lights flickered above them and reflected off of the metallic walls and floor.

Steve pressed his earpiece, "we're in," he hissed into the comms. 

Instead of the normal (temporary) silence, there was a burst of static. Tony sighed. 

"I should have known," this whole place is shielded," said the genius, "it's almost for the better that I didn't bring my suit here. I'm not sure if I could even reach Jarvis at this location."

Their eyes met and Steve nodded towards the center of the room. Tony reached out and gripped his arm.

"Probably a trap," he hissed, brown eyes staring into Steve's.

Steve nodded in agreement, "wouldn't surprise me."

Taking a few more steps into the room, Steve stopped and spun on the spot. Laser fire erupted from around him. Swinging the shield in front of him, he was able to deflect most of it. Blue light flashed in the darkness, illuminating the room. From behind his back, the super-soldier heard the high-pitched whine of his partner's rifle firing followed by the clanking of falling metal.The incoming fire slowed. A few more seconds passed and then more rifle fire. 

The firing stopped. 

"All gone!" Came Tony's triumphant voice. 

Steve cracked a smile. 

"Good job!"

Tony pulled a small device from his pocket. It was a small box with magnets on one side. The other side had red plating, not unlike the Iron Man suit's. Wiring lined some of the plates, emphasizing that the materials had been scavenged and thrown together in a rush.

"Shall we?"

They had just taken several steps towards the lip of the indentation when Tony stopped dead, his knuckles white on the disarming device in his hand. The face that had previously been so confident had paled into a white mask. He whispered something incomprehensible. To Steve, it has sounded like he'd said, " _he knew all along_." 

"What's wrong?" Steve asked, worried at Tony's strange reaction. 

"I need you to do it!" He replied, his face ashen, "that energy field is- never mind."

He shook his head, "maybe I was wrong... about doing this..."

Steve stared at him. There was something very wrong about the way that Tony looked at the missile as if it were suddenly much more of a threat. He'd been managing to keep the mood light the whole time with a balance of sarcasm and crude humor. So far, it had worked well, until now. The only thing that Steve could think of, that could be such a danger, was the soft buzzing that still permeated the air around them. 

"That's what Ultron's robots are here to do... to stop us. But that field... that's for me, after all, I did create him, didn't I?"

Tony's laugh was light and shaky as if he were on the verge of a breakdown. Steve stared at him skeptically, the man was rambling. Turning, he held out the device to Steve.

"Steve, I can't go in there. It's a trap that for me... I set a trap for him, in the same way, several months ago. That missile has is an EMP field around it. I walk into there and I die."

Chills went down Steve's spine.

"Tony, are you sure about this?" 

He nodded, "I got your back, Cap. Don't worry about Ultron. I know he'll come, but I can hold him off. Just place that device!"

Taking the device, Steve turned toward the center of the room. As he began to approach the missile, the super-soldier was painfully aware of Tony behind him. He'd taken several steps before stopping short. Surprised, Tony spun around to look back at him. 

"What?" Tony asked, "you know we're on the clock now?"

"I'd feel more comfortable if you had this," Steve said, tossing his shield to Tony. The other's eyes widened as he easily plucked it out of the air. 

"What, Cap? You don't trust me?" He replied, grinning at Steve. He saw right through the mask. Though he joked, the man was thankful for the extra protection. Steve was sure that he was feeling insecure without the suit and this only proved it.

 

The missile launcher had a large, rectangular housing that had at least ten different kinds of tech connected to it. Before Ultron had made his threat public, no one had really realized how much of a danger he really was. During that lapse, there was no telling how much material the AI had gotten his hands on. It was quite scary to think about. Cables snaked around hundreds of different plates and panels. Altogether it looked like a missile-met-Frankenstein type thing. Steve didn't even know where to start. 

"There should be a housing with light-gray paneling on the side," said Tony from the doorway, sensing his partner's confusion, "looks like a cube with buttons. That's my tech that went missing. My guess is that it controls the EMP. God, what a backstabbing little-" 

"-I see it!" Said Steve, as he spotted the box. Quickly, he attached the device to the metal. Lights began to flash on it, indicating that it was doing its job. 

"Ok, put the device on there, it was designed to hack my tech with the same kind of assimilating factor as Vision and Ultron. Should act as a doorway to - Steve!"

Something was flying towards Steve, something silver. He tried to dodge it but it was too late. A metal mesh exploded in his face, sending him stumbling backward into the missile. The metal coated his left arm, up to his shoulder, binding him to the dark metal explosive. 

 

" _So predictable_ ," came a smooth voice out of the darkness, " _so naive_." 

Ultron drifted down from the ceiling, his vibranium body reflecting off of the small lights in the ceiling. His red eyes bored into Tony. The frame that had started out as a small and friendly-looking robot was replaced by a hulking frame that radiated power. 

" _Hello, father_." 

Tony made a strangling sound and backed away from the robot. He held the shield in a defensive stance and raised his sidearm, his hand shaking slightly. 

" _This will be too easy,_ " the AI sneered as he sent a bolt of energy towards the man. Tony blocked it with the shield but (clearly) was not expecting the enormous kick that the blast had in store. He flew backward and collided with the wall, the shield landing a solid ten feet away. 

Steve could hear himself yelling. He pulled against the mesh that trapped him. For every ounce of strength he used, the more that the mesh seemed to contract around his arm, putting enormous pressure on his shoulder. He could picture his arm ripping off from the strain. 

" _Wait your turn, Captain, I'll be with you shortly,_ " said the robot as it advanced on Tony's motionless figure on the ground.

The polite tone was a huge contrast to the violent ways of its master. The words, intended to pacify the listener, only made Steve struggling harder. At one point, it felt as though his shoulder was about to pop out of its socket. He groaned as he looked back at his arm. All of his efforts had not affected his situation in the slightest. 

In the meantime, Ultron had reached Tony. Towering over his limp form, the robot gloated at the other's pain. It was in that temporary lapse that Tony finally acted. In one swift movement, the human gripped the robot's shin and attached a small circular disc to the vibranium shell. Clearly magnetized, the disc hummed as it hit the metal and refused to budge. Steve knew what it was instantly and almost cheered as he saw it light up. 

_There goes half of our problem!_

There was a howl as Ultron clutched his head. Steve guessed that having one's programming ripped from hundreds of soldiers was not a very pleasant experience. It served the robot right after all he had done. Hundreds of lives had been lost in an effort just to get this far, maybe even more. 

Steve's temporary relief was quickly replaced by fear as he realized that not everything had been disabled (that should have been). For instance, Ultron should  _not_ still be moving. 

Ultron growled, reaching down and gripping Tony by the neck. The man's face paled then began to go a blotchy red as the metallic hand constricted around his windpipe.

" _You worm!"_ The robot was snarling, his metallic face contorted into a mask of anger, " _you've blocked me out! If I were mortal, I would be asking you why you'd do this to your own son! Fortunately, I am immortal. In your world, I am a god, a demon in your eyes, father_. _You hear me? I said immortal!_ "

Bringing his hand down in one fluid motion, Ultron threw Tony across the room. Skidding, Tony landed near the edge of the EMP field, his rifle flying into the field and deactivating. The sidearm also flew off, but Steve did not see where it had gone. He was too focused on what else had happened. 

Steve had cried out, alarmed at how close Tony had come to falling into the EMP field. He remembered Tony's face when the EMP field had come to their knowledge; at the humming that signified its generator and when its threat had become evident. At that exact moment, Steve vowed that he would get free of his bonds and beat Ultron into a thousand pieces for bringing his friend so close to death. 

 

Tony was on his back, his face turned towards Steve. His throat was red from where Ultron's metal fingers had dug into his skin. Scrambling to his feet, he rubbed his neck. Steve imagined that it had to burn like fire after what the robot had done. It would not surprise him if the bruise would last several days or a week. Tony's eyes were wild, full of pain and energy that came from god-knows-where.

 

Temporarily calling off the physical attack, Ultron proceeded to shoot bolt after bolt of energy at Tony. For a guy that a.) didn't like to work out, and b.) wore a suit during almost all of his combat, Tony was doing a damn good job of evading enemy fire. The two seemed to be in a dance, one shooting deadly lasers, while the other dodged around them. Steve couldn't see all of the details through the semi-darkness, but he could see that Tony was clearly headed for something on the floor. Unfortunately, the genius was heading in the opposite direction of the vibranium shield.

"Tony!" Yelled Steve, resuming his struggle with the metallic web, "the shield!" 

Tony stooped down and grabbed hold of something. He was close to the wall, his hair brushing the concrete. Covered in shadows, Steve could not see what it was. It was only seconds later, when the man raised his arm, that Steve saw it was the sidearm. 

Raising the weapon, Tony shot a thin bolt of energy at Ultron, hitting him on the shoulder. While the bolt might have given a living person a shock similar to a taser, the circuitry in the immediate area of impact shorted out. 

Steve was struck by how strong the genius looked during such a difficult time. His hand had steadied and he was calmer. Maybe it was the fact that Ultron was trapped to a single body, or was it the way that he was during a fight all the time? Steve couldn't tell which. All he knew was that Tony was a hell of a lot better in combat than he'd thought. It also helped that Tony had (clearly) tampered with the sidearm, increasing its output and power. He guessed that the weapon had been designed specifically for vibranium. 

Ultron recoiled, clutching his shoulder. This granted Tony a break of several seconds. Thankfully, that was the man needed. 

 

"Steve!" He cried, aiming the weapon at the super-soldier. In a flare of light, the bolt hit the mesh that had been pinning Steve down, dissolving it. 

Immediately, Steve began to disentangle himself from the missile, hating himself for being completely useless over the last few minutes. The mesh was mostly dissolved, so it only one good tug at the remainder of the bond to get it to rip away. He issued a silent prayer that Tony was a good shot, not wanting to think about the resulting shock, should the man have missed his arm. 

The sound of another shot made Steve's blood go cold. That had not been the sound of the sidearm firing and Tony had been quite stationary at the time...

He was almost afraid to look. 

_No, please, no!_

Tony was on his knees, this time clutching a section of skin just above his hip. He was turned away from Steve, so there was not much that he could make out when it came to detail. What he _could_ see was the blood that now pooled on the floor between Tony's knees. Even as he watched, Tony fell onto all-fours, his head drooping. His teeth were gritted together so hard that veins seemed to pop from his brow. His face gleamed with sweat and his palor was once again falling into the "deathly pale" category. 

"NO!" Steve yelled, starting forwards. The remaining strands of metal snapped as he surged towards his friend. 

 

" _Oh, please do keep going_ ," Ultron said, coming up to stand several feet beside Tony, " _I would love an extra reason to kill you_." Ultron raised his hand, his palm glowing with energy, pointing right at Steve's face. 

Screw the gun pointed at his face, screw the AI pointing it at him, screw it all. Steve wasn't stopping for anything.

The palm glowed ominously, starting to whine.

 

Steve was so focused on the robot that he didn't even register that Tony had gotten up. The man was moving towards Ultron...

Just as he realized what the other man was about to do, Steve found his voice. It was too late.

Yelling incoherently, he could only watch...

 

Fire blazed in Tony's eyes as he pulled Ultron into an embrace, his arms wrapped around the robot's metal neck. In one massive effort, he pulled Ultron off balance. The robot tried to disengage himself from Tony but found he could not, for the genius had him in a death-grip. 

To Steve, the pair seemed to fall in slow motion, clearing the small distance between them and the EMP field in milliseconds. The super-soldier was frozen, a statue on the battlefield.

Ultron cried out and squirmed as he saw where they were headed. Given more time, the robot would have succeeded in detaching himself from Tony, but by the time that the robot saw where they were going, it was too late.

 

Tony just seemed to twitch stiffen slightly as the EMP took effect. Ultron just went limp, pulling on Tony with his dead weight. 

 

Together, locked in each other's arms, they crashed to the ground.  

Steve was back in action, racing to Tony's side. With great care, he pried Ultron's silent body off of the man. 

Blood soaked the jumpsuit, pooling around Tony's body and covering his hands. Steve had hoped the EMP field was weak, not strong enough to kill Tony, but of course, it was Ultron who they were talking about. Where a familiar blue light had emanated from the arc reactor, was now emptiness. Clearly, the EMP had done its job.

 

"No..." Steve murmured as he looked down at the person he loved, "nonono."

Deathly pale hands gripped his forearms and slid to meet his fingers. 

"..tsalright," said Tony, his words slurring, "I... knew the bastard would get me... in the end." Brown eyes met blue ones as Tony fixed Steve with a hard look. 

"The missile?" 

"We did it," Steve replied, his eyes beginning to brim with tears, " _you_ did it."

"Gotta appreciate the team, Cap. The _team_..."

Tony had been keeping his head up for the last few minutes and now laid it back. His hand slid from Steve's and rose to his own collar, pulling at it. 

"H-help me," he pleaded, still tugging at it. 

"Alright, alright!" Steve choked. In one movement, he gripped the zipper of the jumpsuit and swiped downwards. 

The arc reactor sat there, a large disc on Tony's chest. Scar tissue forming a latticework of white skin around the metal edges. Steve winced, he'd never seen the arc reactor look so dead before (he'd also never seen Tony's chest exposed either). 

Tony's fingers brushed the reactor.

"...out!" He said, weakly, "we both know that I'm not... not walking... away from this one... Cap."

"I can't do this, Tony," a tear splashed against Tony's chest.

"Take it to Pepper, she'll know what...what to do with it. Steve, promise me..." 

Steve paused, his hand resting on the arc reactor, and brushed a stray piece of hair out of Tony's face. Slowly, the soldier leaned forwards, planting a soft kiss on Tony's forehead. The man closed his eyes and sighed, his skin taking an even paler look, but seeming livelier than it had only seconds ago. 

"Thank...you...Steve..." Tony breathed, his mouth curling upwards into a gentle smile. 

 

There had been too much left unsaid... too much...

Emotion filled his chest and he stifled a sob. 

 

Then Tony put his hand on Steve's, lacing his pale fingers through gloved ones and squeezing. In one burst of energy, he twisted.

 

* * *

 

 

Two weeks later, Steve found himself holding a small glass case. Inside of it, the arc reactor was suspended, glowing a faint blue. 

There, written in silver lettering across the bottom, read the words:

 

_Proof that Tony Stark has a Heart._

 

Then the tears fell down Steve's face. But this time the tears were accompanied by a soft, and sad, smile. 

**Author's Note:**

> I had this fully written and unpublished for a solid three weeks. I didn't realize until yesterday that I had three days left before the draft got deleted. It is a sad fic, written while I felt sad one day :'( 
> 
> Sorry to my friend for taking so long! 
> 
>  
> 
> Any thoughts? I love getting ideas and comments on stuff that I write.


End file.
